BY UMAIR RASOOL AZMI

Pesticides and their Application

Course contents

Pesticide.Classification of Pesticide.• Based on toxicity.• Based on mode of entry.• Based on mode of action.• Based on chemical structure.Qualities of a good pesticide.Pesticide bottle Examination.Field application.• Apparatus.• Precautions.• Hazards.

Pesticide

A pesticide is a chemical used to kill pests.

Pest is any organism that threatens human directly by creating annoyance or indirectly by damaging our crops .

Classification of Pesticide

Insecticide: To kill insects.Herbicide: To kill herbs.Weedicide: To kill weeds.Fungicide: To kill Fungi.Bactericide: To kill Bacteria.Acaricide/Miticide: To kill Mites.Nematocide: To kill Nematodes.Rodenticide: To kill Rodents.

Classification based on Toxicity

Toxicity refers to “degree to which a substance can damage an organism.”

It is measured in LD50 and LC50.

Oral toxins: kill through oral cavity or Stomach.Dermal toxins: kill through Skin.Respiratory toxins: kill through respiratory

System.

Classification based on Mode of Entry

How a chemical enters into the insect body cavity?

Stomach poison.Contact Poison.Systemic Poison.Fumigant Poison.Trans-laminar Poison.

Classification based on Mode of Action

How a pesticide acts after entering in body of insect?

• Nerve Poison.• Muscle Poison.• Physical Poison.• Metabolic Poison.

Classification based on chemical structure

Based on chemical structure Pesticides are of five types:

1. Organochlorine (DDT, Chlordane).2. Organophosphate (Profenofos, Chloropyrifos).3. Carbamates (Carbaril, Carbosulfan, Carbofuran).4. Pyrethrides (Bifenthrine, Lambda-cyhalothrine).5. New chemistry (Imedacloprid, Acetamiprid, Leufenuron,

Amamactin etc.).

Classification based on Formulation

Formulation is the mixture of active and inactive ingredient in a specific proportion for specific purposes.

Solid FormulationsLiquid FormulationsGas Formulations

Solid Formulations

Soluble PowderWet-able PowderDustGranulesBaitsSlow Release Tablets

Liquid Formulations

Emulsifable ConcentrateFlow-able ConcentratesAerosolSolution• Low Concentrate• High Concentrate• Ultra Low Volume

Gas Formulations

FogSmoke

Qualities of a Good PesticideHighly potent.Quick Knockdown Effect.Broad Spectrum Activity.Cheap.Compatible with other pesticides.Non inflammable/ Non corrosive.Not off taste the crop.Easy Formulation.Optimum Residue Persistence.Least environmental pollution.Non-Phototoxic.Low possibility of insect Resistance.Activation in insects.Safe for beneficial Insects.

Examining Pesticide Bottle Label

Apparatus for Application

About Nozzles.Knap Sack Sprayer.ULV Sprayer.Compressed Sprayer.Boom Sprayer.

Nozzles

Nozzle Spray Angle Pressure (bars)

Drop size Target

Hollow Cone 65-110 3 100-150 Cotton foliage

Solid Cone 25-70 3 100-200 Spot treatment

Variable Cone

0-110 3-10 100-200 Orchards

Flat-Fan 80-110 2-3 200-250 Pre-emergence

Flood Jet 90-140 1-2 Less than 250

Post-emergence

Dual Fluid 90-140 1-2 Less than 250

Foliage emergence

Knap Sack Sprayer

Components:• Main body• Straps• filler hole• Pump• Pump handle• Pressure chamber• Hose pipe• Trigger• Lance• Nozzle

Working: When a stroke is made, pressure is created in pressure

chamber. When trigger is pushed, the pesticide solution is ejaculated with a pressure. The drop size depends upon the type of nozzle attached.

Ultra Low Volume Sprayer

Vegetable oil is used instead of water.

It is battery operated.

Drop Drift chances are very low due to high density of oil.

Pesticide consumption is very low 0.6-4.7liters per acre.

Compressed Sprayer

It is used in Gardens. It has a big lance and also

has high pressure as compared

to a normal sprayer.

Boom Sprayer

It is used at large scale. Battery operated. High pressure pump. Auto-leveling mechanism in field.

Precautions

Pesticides are chemicals use them carefully.Wear gloves, cowboy shoes and mask while application.Wear the straps properly and keep lance at 1ft. to the

height of the plant.Only use a pesticide according to recommended dose.Do not make mixture of any kind of pesticides unless it is

recommended.When using Herbicides/Weedicides spray a row only

once as these chemicals can burn plants.After application wash the tank properly.In case of any personnel accident, take the victim to a

doctor immediately along with pesticide bottle.

Hazards

Killing of natural enemies.Insect Resistance problems.Residual hazards.Upsetting of natural balance.• Air pollution–-water pollution—Soil pollution.

Hazards to personnel and domestic animals.High cost of pesticides, labour, Maintenance of

equipments.